1. FIELD OF THE INVENTION
This invention relates to a collision safety device for vehicles, and more particularly, to an improved vehicle impact collision absorber that transforms an impact force upon a vehicle body into a lifting of the vehicle body, which lifting force is absorbed by the weight, or normal force, of the vehicle body. The force required to lift a vehicle body and the vehicle's reactive normal force or weight coact to dissipate the impact force by diverting the collision impact energy to the raising of the vehicle, thereby reducing the likelihood of damage to the vehicle and its occupants.
2. PRELIMINARY DISCUSSION
An impact upon an automotive vehicle can be quite traumatic, both to the occupants and the vehicle's structural integrity.
Low speed impacts, in the nature of impacts occurring at from 0 to 20 miles per hour, tend to result in less damage all around.
Even at a relatively low speeds, however, such as between 5 and 15 miles per hour, the amount of damage to a bumper or the like can be quite extensive.
Impact absorbers today, i.e. bumpers, impact bars and the like, regardless of where they might be positioned, are designed to withstand a minimal impact collision in the range of 0 to 5 miles per hour without noticeable or serious structural deformation. Low to mid speed collisions usually result in additional structural damage to a vehicle frame, and with the current use of so-called "crumple zones," such damage can be considerable. It is known that the greater the impact force absorbed by the vehicle body and frame, the less impact force will be experienced by the occupants. "Crumple zones" and the like are wonderful at dissipating force, however, a relatively minor impact can result in a very expensive repair, particularly if such impact causes a disproportionate amount of the vehicle body or frame to "crumple." While vehicles simply aren't built the way they used to, i.e. with steel ship-like hulls, one of their primary purposes is to protect the passengers from any type of impact, whether it be a simple rock ejected from the wheel of a tractor trailer, or whether it be a jack-knifed tractor trailer skidding down a roadway. Consequently, any device that improves the chances of reduced harm to vehicle and passengers during an impact situation should be looked favorably upon by all.
Impact force absorption generally occurs in one of three ways. First, as demonstrated by dented bumpers, bent frames or progressively crumpling "crumple zones," an impact force can be absorbed through the mechanical, structural deformation of the body being impacted. This type of impact absorption is usually the most expensive and aesthetically unappealing. Another type of impact absorption is absorption into the opposite body, i.e. a strong rigid bumper may transfer a considerable amount of the impact into another body, damaging that body. If the other body is "immovable," such as a tree, wall, telephone pole or the like, however, the sudden stop may impair the occupants of the vehicle. A third type of impact force absorption occurs through the transformation or transferral of such impact force to a force "sink," or away from the body being impacted.
The transferral or bypassing of energy to avoid or prevent contact with a particular object is known throughout the scientific world. A lightning rod is a prime example of this concept, where the rod transfers a high-magnitude burst of electrical energy through a house to the "ground," with the ground serving as an energy sink. Lightning rods are used primarily to protect the occupants and electrical system of a dwelling, since a direct impact upon a house without an energy transfer means would wreak havoc on any electrical appliance, the wiring system in general, and potentially the occupants of the dwelling.
The device of the present invention operates under a similar energy transfer theory, although the focus is on the transfer of moving mechanical, or kinetic energy, not electrical energy. Kinetic energy generated during a vehicle impact is usually transmitted both into the impacted vehicle and back into the impacting vehicle or other object impacted. Energy imparted to the impacted vehicle generally tends to cause such vehicle to either move in a direction directly opposite the impacting force, or in an oblique direction, i.e. upward, downward or to the side, or a mixture of all three. A downwardly directed impact force tends to be partially transmitted through the vehicle and into the ground, where the ground enhances the dissipation of the force. Since the ground is relatively immovable, however, considerable reactive forces return to the vehicle.
An upwardly directed impact force, however, tends to cause the vehicle to lift, which is overall more difficult to achieve due to the normal force or weight of the vehicle acting opposite the lifting force. In other words, due to the gravitational pull of the earth upon a vehicle, i.e. its weight, it is much more difficult to lift a portion of a vehicle than it is to cause the vehicle to move downwardly or even to the side. Consequently, it takes considerable more energy to cause a vehicle to move in an upward direction than in a downward direction.
The present inventor applied this principle to vehicle impact situations, and designed a device that would transfer an impact force into a lifting force, with such lifting force being dissipated rather quickly due to its interaction with the weight forces of a vehicle. The broad concept of a vehicle absorption device that transforms impact energy into lifting energy is, however, quite old. Early designs illustrate, for example, the direct transformation of a horizontal impact energy upon a bumper or the like directly to the ground through a separate and distinct mechanical linkage. Other devices illustrate means to transform an impact energy into a lifting motion that create both a braking force and a dissipating force with respect to the impacted automobile. Both safety considerations and energy transformation issues have led to the establishment of a well developed class of art in the files of the U.S. Patent and Trademark Office, which class of art is generally directed to or demonstrative of a collective desire to overcome several particular problems using consistent or similar methods or means, one of which problem is the dissipation of collision energy by using such energy to raise one of the impacted or vehicles.
It can not be overlooked, however, that while the Patent Office files include a large number of references designed to absorb collision impacts in the same general manner as the present inventor, none of such references appear to have experienced significant and/or lasting commercial success.
3. DESCRIPTION OF RELATED ART
As noted above, the prior art related to impact absorption systems is relatively well developed, with some of the more relevant references dealing with angled energy transfer systems listed below:
______________________________________ U.S. Patents Number Inventor Issue Date ______________________________________ 1,177,340 J. B. Klein 03-28-1916 1,684,776 S. Nishida et al 09-18-1928 1,718,658 K. Matsumoto 06-25-1929 2,966,225 F. M. Carroll 12-27-1960 3,056,462 P. Graham 10-02-1962 3,495,676 P. Graham 02-17-1970 3,618,693 P. Graham 11-09-1971 3,349,865 A. T. Deutsch 10-31-1967 3,383,077 N. Noviello, Jr 05-14-1968 3,472,332 E. M. Halvajian 10-14-1969 3,806,184 J. O. Dean 04-23-1974 3,822,907 H. Appel et al 07-09-1974 4,065,169 A. Yamanaka 12-27-1977 4,143,735 S. L. Schlanger 03-13-1979 4,566,555 S. L. Schlanger 01-28-1986 4,826,209 E. T. Farris 05-02-1989 5,226,685 Y. Chen 07-13-1993 5,507,546 J. D. Holley 04-16-1996 5,570,826 L. V. Garbes et al 11-05-1996 5,697,467 M. S. Howard 12-16-1997 ______________________________________
Absent from the above is the present inventor's original design, embodied in his initial U.S. Pat. 5,257,842, issued to S. Sherno on Nov. 2, 1993, entitled "Collision Impact Absorber." The original design consisted of a pivoted lever attached to the frame of an automobile, such that in a collision, such lever receives a direct impact resulting in a downward force upon the lever arm, and a reactive upward force upon the vehicle, the rotation of the arm being restrained somewhat by a spring attached between the lever arm and the vehicle. The pivot connection is located at the end of the arm, while the spring or recoil is situated between the impact and the pivot point. At rest, the lever arm is mounted with a downward inclination or angle from horizontal, such that a horizontal force upon the end of the lever arm is immediately translated into a clockwise rotation at the pivot point of the lever, which clockwise rotation results in upward movement of the vehicle. There is also provided a stop which maintains the lever arm at a fixed angle to horizontal when at rest.
The original Sherno design was ingenious because it was so simple. The prior art is teeming with designs that are quite and even incredibly complicated, and therefore, difficult to implement without a radical change or substantial additions to a vehicle structure. The original Sherno design utilized a single force transmission member, which created a direct transfer of an impact force into a lifting force. Other inventions required complicated linkage systems, with at least two, three or more force transmissions between the point of impact and the lift upon the vehicle.
The original Sherno design is, however, not without its shortcomings. The placement of the original lever arm resulted in its immediate rotation upon impact, which caused the vehicle to deflect even under the most minimal of impact conditions, i.e. at less than 5 miles per hour for example. Furthermore, the impact end of the lever arm is situated below and/or in front of the bumper, which can appear somewhat unsightly and out of place. It would be more desirable, for example, to have the impact end of the collision absorber located before or behind the bumper, or even integrally attached to a bumper, which placement would enhance the function of the original bumper, and at the same time hide the lever arm from view. Locating the lever arm at or below the bumper also results in an increased angle of the lever arm to the horizontal at rest, which is one of the reasons why the original lever arm initiated immediate rotation upon impact.
Another shortcoming of the original Sherno design, as discussed briefly above, is its inability to undergo a minimal impact without immediately imparting a rotation to the impacted body. In relatively low speed impacts, it would be desirable if there was some way to prevent an immediate rotation of the lever arm, where such rotation would be deemed ineffective or plainly unnecessary. Furthermore, in relatively low speed impacts, it would also be desirable, for example, to have the lever arm deflect rearward, or away from the impacting force, a certain distance prior to initiating rotation, where such rearward deflection would be controlled by a deflection means related to the amount of force imparted to the end of the collision absorber and further related to the length of the lever arm. In other words, it would be desirable if the lever arm were equipped with some means that allowed it to deflect a certain amount for a predetermined amount of force in order to absorb and dissipate a limited amount of force or energy, but after attaining such limited force, such lever arm would initiate rotation with respect to a vehicle body and cause such vehicle to lift as before, effectively absorbing additional energy. Such predetermined amount of force mentioned above might be related to the structural properties of the deflection means, coupled with the force properties of the impacting body, and it might also be desirable to have such structural properties of such deflection means variable, particularly if the collision absorber is going to be incorporated into different vehicles or the like, having different weights, etc.
The original Sherno design, therefore, suffers from several structural shortcomings, none of which have been addressed by the prior art before or since. In fact, the prior art issued subsequent to the original Sherno patent, as known by the inventor, has failed to present a collision impact absorber having any of the properties of the original Sherno design, or a collision impact absorber that improves upon such design. There exists a need, therefore, to provide an improved collision impact absorber having all of the desirable improvements or features mentioned above.